My GPS approach showed a 200 foot altitude discrepancy on a Citation Mustang

Had a Citation Mustang come through last month with the Garmin G1000 showing weird altitude numbers during an ILS. Pulled the pitot static lines and found a cracked fitting behind the avionics bay panel. Replaced it with a steel fitting instead of that plastic one from the factory. Anyone else run into those cheap plastic pitot fittings failing on the 500 series?

2 comments

2 Comments

iris3941mo ago

Had a similar issue on a Cessna 310 last year, but it wasn't the pitot static. It was a clogged static port from some wasp nest that got blocked during a rainstorm. The altimeter bounced all over the place on approach. We ended up having to replace the whole static line because the bugs had gotten into the tube and made a mess. It's amazing how something so small can mess up your numbers. Those Garmin screens are sensitive, but the hardware underneath is still pretty basic. Always double check those lines before throwing parts at it.

danielh811mo ago

Seen this exact thing on a couple different plane types now. It's always the cheap plastic factory fittings that crack right where the barb meets the body, never the metal replacements. Same story with a lot of stuff these days - they save a few cents and it causes a way bigger headache later.